JPH0848874A - Resin composition - Google Patents

Abstract

PURPOSE:To obtain the subject inexpensive composition, having high rigidity, impact and heat resistances and good in resistance to a road surface antifreezing agent by blending a specific copolyamide with a modified polyolefin and a filler. CONSTITUTION:This resin composition comprises a blend prepared by blending (A) 100 pts.wt. copolyamide comprising (i) a recurring unit of formula I and (ii) a recurring unit of formula II (R is a 6C aliphatic group; R' is a 4C aliphatic group) at (10-90) to (90010) weight ratio of the components (i)/(ii) with (B) 1-100 pts.wt. modified polyolefin and (C) 1-100 pts.wt. filler. Furthermore, e.g. (i) an alkylene terephthalamide synthesized from (a) a 6C aliphatic alkylenediamine, especially 1,6-diminohexane, etc., and (b) terephthalic acid and (ii) a condensate formed from the component (a) with (c) a 6C aliphatic alkylenedicarboxylic acid, especially adipic acid, etc., are preferably used as the component (A).

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention has good resistance to a road surface antifreezing agent containing a metal halogen compound such as calcium chloride, magnesium chloride or zinc chloride as a main component, and has excellent impact resistance, rigidity and heat resistance. The present invention relates to a polyamide underhood component for automobiles.

[0002]

2. Description of the Related Art In recent years, in the automobile industry, there has been a remarkable tendency to use conventional metal parts as resins for the purpose of weight reduction for improving fuel efficiency, rust prevention and sound insulation. Among them, polyamide resins have excellent heat resistance, oil resistance, moldability, and toughness, so they are used in underhood parts of automobiles such as cooling fans, radiator tank tops and bases, cylinder head covers, and oil pans. , Gears, valves, brake pipes, tubes for fuel pipes, other exhaust gas system parts, and various functional parts such as electrical system parts such as connectors.

In general, roads in cold regions are sprayed with a large amount of antifreezing agent containing calcium chloride, magnesium chloride, zinc chloride or the like as a main ingredient in order to prevent road surface freezing, especially in winter. There is a need for materials that are highly resistant to agents.

On the other hand, nylon 6 and nylon 66
Polyamide resin composition in which nylon 11 or nylon 12 is blended with or a reinforced product thereof (JP-A-60-8806)
6, JP-A-57-212252), a polyamide resin composition obtained by blending an aliphatic polyamide and an aromatic polyamide and their reinforced products (JP-A-58-120665, JP-A-58-53950, etc.), and polyamide and phenol. Resin compositions prepared by blending resins and modified polyolefins and reinforced products thereof (JP-A-60-188456, JP-A-6-186456)
1-76540, etc.) have been proposed.

[0005]

With the recent rise in the temperature of the engine room of automobiles and the progress of microelectronics due to technological innovation, there has been a demand for a molding material that can withstand use in a higher temperature atmosphere.

However, these resin compositions lack mechanical strength and heat resistance such as tensile strength and flexural modulus as a metal substitute material, and have high material cost. Only applied.

[0007]

SUMMARY OF THE INVENTION In light of the above circumstances, the present inventors have proposed an underhood component for automobiles that is inexpensive, has good resistance to a road deicing agent, and has excellent impact resistance, rigidity and heat resistance. As a result of investigation, they have found that a specific terephthalic acid-containing polyamide resin composition can solve all the problems, and arrived at the present invention.

That is, the present invention is a repeating unit

[Chemical 3] And repeating units

[Chemical 4] (Wherein R represents an aliphatic group having 6 carbon atoms and R'represents an aliphatic group having 4 carbon atoms), and the weight ratio of (I) / (II) is from 10/90 to 90/10. Copolyamide [A]
Modified polyolefin [B] 1 to 100 parts by weight
Resin composition for automobile underhood parts, which is composed of a mixture of 100 parts by weight and 1 to 100 parts by weight of a filler [C], and an underhood part for automobiles and a cylinder head cover for vehicles formed by molding the resin composition. Is.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The copolymerized polyamide resin [A] of the present invention is (I) an aliphatic alkylene terephthalamide synthesized from an aliphatic alkylene diamine having 6 carbon atoms and terephthalic acid, and optionally (II ) A condensate formed from an aliphatic alkylenediamine having 6 carbon atoms and an aliphatic alkylenedicarboxylic acid having 6 carbon atoms. Specific examples of the aliphatic alkylenediamine having 6 carbon atoms include 1,4-diamino-1,1-dimethylbutane and 1,4-diamino-1.
-Ethylbutane, 1,4-diamino-1,2-dimethylbutane, 1,4-diamino-1,3-dimethylbutane,
1,4-diamino-1,4-dimethylbutane, 1,4-
Examples thereof include diamino-2,3-dimethylbutane, 1,2-diamino-1-butylethane, 1,5-diamino-2-methylpentane, 1,6-diaminohexane and the like. Among these alkylenediamine components, 1,6-diaminohexane is preferable. Moreover, adipic acid is illustrated as a specific example of the C6 aliphatic alkylenedicarboxylic acid component unit.

The copolymerization ratio of the copolymerized polyamide of the present invention must be such that the weight ratio (I) / (II) is in the range of 10/90 to 90/10, preferably 20/80 to 9.
It is 0/10, more preferably 30/70 to 90/10. If the copolymerization ratio is less than 10/90, the resistance to metal halides decreases, and the road deicing agent resistance decreases, which is not preferable. The degree of polymerization of the polyamide used here is not particularly limited, and the relative viscosity (ηr) of a 1% sulfuric acid solution at 25 ° C. is usually 1.5 to
Any of those in 5.0 can be used.

The method for producing the copolyamide of the present invention is not particularly limited, but the water vapor pressure is 20 kg / cm ² -G or less, 150 to 320 while stirring the aqueous solution of the monomer or salt of the components (I) to (II). Heating at ℃, ηr = 1.01-1.
A method of preparing a low-order condensate of 6 and subjecting it to solid-phase polymerization at a temperature below the melting point or a method of increasing the degree of polymerization using a single screw or twin screw extruder with a vent port is simple and suitable. There is.

According to the present invention, the presence of a phosphorus-based catalyst is effective for obtaining good pellets having a high degree of polymerization in the melt extrusion step, and the addition amount is 0.02 to 2 w relative to the lower condensate.
t% is preferable, and more preferably 0.05 to 1.2 wt.
%. Specific examples of phosphorus compounds include H ₃ PO ₄ and H
₃ PO ₃ , H ₃ PO ₂ , H ₄ P ₂ O ₇ , NaH ₂ PO _{4
· 2 H 2 O, Na 2} HPO 4 · 12H 2 O, Na 3 PO
₄・ 12H ₂ O, NaH ₂ PO ₄・ H ₂ O, Na ₄ P ₂
O ₇ · 10H ₂ O, Na ₂ H ₂ P ₂ O ₇ · 6H ₂ O, N
a ₅ P ₃ O ₁₀ , C ₆ H ₅ P (OH) ₂ , C ₆ H ₅ PO
(ONa) ₂ , C ₆ H ₅ PO (OH) ₂ , Mn (H ₂ P
O _{2) 2,} and the like _{(C 6 H 5 O) 3} P. Preferred are H ₃ PO ₄ and H ₄ P ₂ O ₇ . The addition method of the phosphorus compound is not particularly limited, and a method of preparing a low-order condensate, or a method of previously blending with the low-order condensate and melt-extruding is convenient and suitable.

The modified polyolefin [B] of the present invention means ethylene, propylene, butene-1, pentene-1, 4-.
Methylpentene-1, isobutylene, 1,4-hexadiene, dicyclopentadiene, 2,5-norpornadiene, 5-ethylidenenorporne, 5-ethyl-2,5
-Norbornadiene, 5- (1'-probenyl) -2-
A carboxylic acid group, a carboxylic acid ester group, a carboxylic acid metal group, a carboxylic acid anhydride group, a carboxylic acid amide group is added to a polyolefin obtained by radically polymerizing at least one olefin selected from norbornene, butadiene, isoprene and styrene. A modified polyolefin obtained by introducing a component (hereinafter, referred to as a functional group-containing component) into a monomer having at least one functional group selected from an imide group and an aminohydroxyethyl group.

Examples of the functional group-containing component include acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, crotonic acid, methylmaleic acid, methylfumaric acid,
Mesaconic acid, citraconic acid, glutaconic acid and metal salts of these carboxylic acids, methyl hydrogen maleate, methyl hydrogen itaconate, methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, (meth)
2-ethylhexyl acrylate, hydroxyethyl (meth) acrylate, aminoethyl (meth) acrylate, dimethyl maleate, dimethyl itaconic acid, maleic anhydride, itaconic anhydride, citraconic anhydride, endobicyclo- [2,2,2 [Alpha], [beta] -unsaturated carboxylic acid derivatives such as 1] -5-heptene-2,3-dicarboxylic acid, endobicyclo- [2,2,1] -5-heptane-2,3-dicarboxylic acid anhydride and the like, and here The α, β-unsaturated carboxylic acid, its ester, its anhydride, glycidyl (meth) acrylate, (meth) acrylic glycidyl ether, epoxy-containing saturated compounds such as vinyl glycidyl ether, ammonia, methylamine, ethylamine, Butylamine, hexylamine, dodecylamine, oleylamine, stearyl Min, cyclohexylamine,
Benzylamine, aniline, naphthylamine, dimethylamine, diethylamine, methylethylamine, dibutylamine, distearylamine, dicyclohexylamine, ethylcyclohexylamine, methylaniline, phenylnaphthylamine, melamine, ethanolamine,
3-amino-1-propanol, diethanolamine,
Morpholine, α-amino-2-pyrrolidone, α-amino-ε-caprolactam, α-monomethylamino-ε-caprolactam, α-monoethylamino-ε-caprolactam, α-monobenzylamino-ε-caprolactam,
Examples thereof include N-substituted amide compounds, N-substituted imide compounds and N-substituted hydroxyethyl compounds obtained by adding a nylon oligomer having a terminal amino group.

The method of introducing the functional group-containing component is not particularly limited, and a method of mixing with the main component olefins for copolymerization, or a method of graft introduction into the polyolefin by using a radical initiator is used. be able to. The amount of the functional group-containing component to be introduced is usually 0.001 to 40 mol%, preferably 0.01 to 35 mol%, based on the whole modified polyolefin.
If the amount of the functional group-containing component is less than 0.001 mol%, the affinity between the modified polyolefin and the copolyamide will be insufficient,
The impact resistance imparting effect tends to be insufficient. On the other hand, when the amount of the functional group-containing component exceeds 40 mol%, side reactions such as gelation tend to occur easily.

Specific examples of the modified polyolefin particularly useful in the present invention include ethylene / (meth) acrylic acid copolymers, and sodium, lithium, zinc, or some of the carboxylic acid moieties in these copolymers. Salted with calcium, potassium, etc., ethylene / (meth)
Methyl acrylate copolymer, ethylene / (meth) ethyl acrylate copolymer, ethylene / ethyl (meth) acrylate-g-maleic anhydride copolymer (“g” represents a graft, the same applies hereinafter), ethylene / Methyl (meth) acrylate-g-maleic anhydride copolymer, ethylene /
Ethyl (meth) acrylate copolymer, ethylene / ethyl acrylate-g-maleimide copolymer, ethylene / ethyl acrylate-g-phenylmaleimide copolymer and partially saponified products of these copolymers, ethylene / propylene g -Maleic anhydride copolymer, ethylene / butene 1-g
-Maleic anhydride copolymer, ethylene / propylene /
1,4-hexadiene-g-maleic anhydride copolymer,
Ethylene / propylene / dicyclopentadiene-g-maleic anhydride copolymer, ethylene / propylene / 2,5
-Norbornadiene-g-maleic anhydride copolymer, ethylene / propylene-g-N-phenylmaleimide copolymer, ethylene / butene-1-g-N-phenylmaleimide copolymer, styrene / butadiene-g-maleic anhydride Examples thereof include acid copolymers and styrene / maleic anhydride copolymers.

The amount of the modified polyolefin compounded is 1 to 100 parts by weight based on 100 parts by weight of the copolyamide,
It is preferably in the range of 5 to 90 parts by weight. Compounding amount is 1
If the amount is less than 100 parts by weight, the resulting molded article lacks impact resistance, which is not preferable. On the contrary, if the amount exceeds 100 parts by weight, the molded article lacks heat resistance, which is not preferable.

The filler [C] referred to in the present invention is glass fiber or beads, talc, carion, wollastonite, mica, silica, alumina, diatomaceous earth, clay, gypsum, red iron oxide, graphite, titanium dioxide, Powdery or plate-like inorganic compounds such as zinc oxide, copper, and stainless steel, other polymer fibers (carbon fibers), and the like, and preferably glass fibers. Particularly preferred glass fibers are glass chopped strands and glass threads having a diameter of about 3 to 20 μm. The compounding ratio of the filler is 1 to 1 with respect to 100 parts by weight of the copolyamide.
It is necessary to be in the range of 00 parts by weight, preferably 5 to 90 parts by weight, particularly preferably 10 to 90 parts by weight. If the blending amount of the filler exceeds 100 parts by weight, the fluidity at the time of melting is deteriorated, which makes it difficult to injection-mold a molded product, and is also unfavorable because the appearance of the molded product is deteriorated.

There is no particular limitation on the method of blending the filler with the copolymerized polyamide of the present invention, and any known method can be used. Specific examples of the mixing method include a method in which pellets of copolyamide are dry-blended with a modified polyolefin and a filler, and the resulting mixture is melt-kneaded with a single-screw or twin-screw extruder.

The underhood component for automobiles of the present invention is molded by subjecting the above polyamide resin composition to a known molding method such as injection molding, extrusion molding, blow molding or vacuum molding. Cooling fans are examples of molded products.
Examples include radiator tanks, cylinder head covers, oil pans, gears, valves, brake pipes, fuel pipes, other tubes, pipes, other exhaust gas system components, and connectors.

The molded parts thus obtained may be subjected to secondary processing such as painting, vapor deposition and lamination.

The resin composition for underhood parts for automobiles of the present invention may contain other components such as pigments, dyes, heat-resistant agents, catalysts, and antioxidants in any step as long as the moldability and physical properties are not impaired. Agent, weathering agent, lubricant,
Crystal nucleating agents, antistatic agents, plasticizers, other polymers and the like can be added.

[0023]

The present invention will be described in more detail with reference to the following examples. Various properties in the examples and comparative examples were measured by the following methods. (1) Melting point (Tm) The temperature showing the maximum value of the melting curve obtained by measuring 8 to 10 mg of a sample using DSC (PERKIN-ELMER type 7) at a heating rate of 20 ° C / min is defined as (T). . Heat 8 to 10 mg of the sample at a heating rate of 20 ° C / min to give T + 2.
Hold at 0 ° C. for 5 minutes, then cool to 30 ° C. at a cooling rate of 20 ° C./min, hold at 30 ° C. for 5 minutes, then repeat 2
Heat to T + 20 ° C at a temperature rise of 0 ° C / min. The maximum value of the melting curve at this time was defined as the melting point (Tm). (2) Calcium chloride resistance Treatment of underhood moldings immersed in warm water at 90 ° C for 24 hours, then left in a gear oven at 100 ° C, and spraying 50% calcium chloride solution in water drops every hour. Was set as one cycle, and the number of cycles until cracking occurred in the molded product was measured. (3) Appearance of molded product The surface of the molded product was observed to be rough, air bubbles, color tone and gloss. ◯: Glossy and smooth surface. Δ: The surface is smooth although the gloss is reduced. X: There is no gloss and the surface is rough. (4) The physical properties of the molded product were measured by the following methods. Tensile Strength: ASTM-D638 Bending Strength: ASTM-D790 Bending Elastic Modulus: ASTM-D790 Izod Impact Strength: ASTM-D256 Heat Deformation Temperature (HDT): ASTM-D648 Load 4.6 kgf / cm ² Load 18.6 kgf / cm ²

Example 1 5.89 kg of terephthalic acid and 6 of hexamethylenediamine
6.37 kg of a 4.5 wt% aqueous solution, 10.00 kg of hexamethylene ammonium adipate (66 salt) and 6.66 kg of ion-exchanged water were charged in a 0.05 m ³ batch type pressure gun rear kettle, and the same method as in Example 1 was used. The next condensate was made.
The obtained low-order condensate has Tm = 296 ° C. and ηr = 1.26.
Met. This low-order condensate was vacuum dried at 100 ° C. for 24 hours, and then melt-extruded using a 30 mmφ vent type twin-screw extruder at a melting point of 20 ° C. to obtain ηr =
Pellets of 3.25 and Tm = 295 ° C were obtained. 100 parts by weight of the pellets, 43 parts by weight of glass fiber chopped strands having a length of 3 mm and a diameter of 13 μφ and 2 mol% of maleic anhydride were contained, and a melt index of 7 g /
After dry blending 20 parts by weight of ethylene / ethyl acrylate / maleic anhydride copolymer for 10 minutes, 30 mmφ
Was melt-kneaded and pelletized under the temperature condition of Tm + 20 ° C.

After vacuum-drying the pellets, the temperature of the cylinder is Tm + 20 ° C. and the mold temperature is 80 ° C. by an injection molding machine.
ASTM standard physical property test piece and length 450m
A box-shaped cylinder head cover having m, width of 200 mm, height of 80 mm and wall thickness of 3.5 mm was formed. Table 1 shows the results of evaluation of mechanical properties, heat distortion temperature, and resistance to metal halides using the molded pieces obtained here.

Examples 2 to 3 The characteristics of test pieces and molded articles obtained by carrying out the same operation as in Example 1 by changing the type of polyamide, the type of modified polyolefin, the type of filler, the compounding amount, etc. The results obtained are shown in Table 1.

[0027]

[Table 1]

Comparative Example 1 3 parts in diameter per 100 parts by weight of nylon 66 pellets
m, diameter 13μφ glass fiber chopped strand 4
A test piece and a cylinder head cover were prepared in the same manner as in Example 1 by dry blending 3 parts by weight. Table 2 shows the evaluation results. The calcium chloride resistance of this molded product was poor.

Comparative Example 2 Nylon 12 (100 parts by weight) was dry-blended with glass fiber chopped strands (65 parts by weight), and a test piece and an underhood component were prepared in the same manner as in Example 1. When the physical properties of the obtained test piece were evaluated, as shown in Table 2, the rigidity and heat distortion temperature were insufficient.

Comparative Example 3 7.21 kg of terephthalic acid and 6 of hexamethylenediamine
0.05m of 4.5 wt% aqueous solution 7.80 kg, ε-caprolactam 5.25 kg and ion exchange water 6.10 kg
^After being charged in a batch type pressure polymerization kettle of No. 3, nitrogen substitution was sufficiently performed, heating was continued under a steam pressure of 17.5 kg / cm ² -G. After the temperature was raised to 230 ° C. over 5 hours with stirring, the reaction was further allowed to proceed at 230 ° C. to 245 ° C. for 30 minutes, the stirring was stopped, and the differential pressure from the bottom of the polymerization vessel was 17.5 kg / cm ² −.
The low-order condensate was extracted into water with G. The obtained low-order condensate had Tm = 303 ° C. and ηr = 1.21. This low-order condensate was dried under vacuum at 100 ° C. for 24 hours, and then dried under N ₂ blow atmosphere using a kneader with an internal volume of 30 L to 250.
Solid-state polymerization was carried out for 3 hours under a temperature condition of ° C to obtain a high degree of polymerization polymer. The obtained polymer has ηr = 2.75 and Tm =
It was 303 ° C.

43 parts by weight of glass chopped strands having a length of 3 mm and a diameter of 13 μφ were dry blended with 100 parts by weight of the highly polymerized pellets, and a molded product was prepared by the method of Example 1, and the evaluation results were shown. The results are shown in Table 2. The impact resistance was low.

Comparative Example 4 Ethylene / propylene / butene-1-containing 2 mol% of maleic anhydride based on 100 parts by weight of the highly polymerized polymer obtained in Comparative Example 3 and having a melt index of 0.4 g / 10 min. 20 parts by weight of the g-maleic anhydride copolymer was dry blended, a molded product was prepared by the method of Example 1, and the evaluation results are shown in Table 2. Flexural modulus was low.

Comparative Example 5 With respect to 100 parts by weight of the high degree of polymerization polymer of Comparative Example 3,
The same copolymer and glass fiber as in Example 1 were dry blended, a molded product was prepared by the method of Example 1, and the evaluation results are shown in Table 1. Polymer used in this comparative example (nylon 6T
/ 6) has a higher melting point than the polymer of Example 1 (nylon 6T / 66) but has a heat distortion temperature (HDT (18.6 kgf
/ cm2)) and calcium chloride resistance were low.

[0034]

[Table 2]

[0035]

INDUSTRIAL APPLICABILITY The underhood parts for automobiles obtained from the present invention have high rigidity, impact resistance and heat resistance, and moreover have resistance to a road surface antifreezing agent containing a metal halogen compound such as calcium chloride or zinc chloride as a main component. It is good.

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Claims (3)

[Claims] 1. A repeating unit: And repeating unit (Wherein R represents an aliphatic group having 6 carbon atoms and R'represents an aliphatic group having 4 carbon atoms), and the weight ratio of (I) / (II) is from 10/90 to 90/10. Copolyamide [A]
Modified polyolefin [B] 1 to 100 parts by weight
A resin composition for an automobile underhood component, which comprises 100 parts by weight and 1 to 100 parts by weight of a filler [C]. 2. An underhood component for an automobile, which is formed by molding the resin composition according to claim 1. 3. A cylinder head cover for an automobile, which is formed by molding the resin composition according to claim 1.